Abstract:
A tension in the unitarity of the first-row of the CKM matrix has emerged in recent years. This "Cabibbo anomaly" has motivated a renewed scrutiny of the QED corrections applied to low-energy precision beta decays.
In this talk I will explain how this problem can be formalized in effective field theory, ultimately descending to a heavy-quark-like effective theory of point-like nuclei. I will outline recent progress on the control of high order QED corrections in this point-like theory, including an understanding of the all-orders structure for the Z-enhanced Coulomb-corrections, and comment on implications for the extraction of |V_{ud}| and the interpretation of beta-decay experiments.
Join Zoom Meeting - Meeting ID: 933 4269 3866 Passcode: 185096
univienna.zoom.us/j/93342693866